Replanting of broadleaved trees alters internal nutrient cycles of native and exotic pines in subtropical plantations of China  

作　　者：Yong Lin Chengkang Xia Gaoyang Wu Fangchao Wang Shengnan Wang Yuanqiu Liu Fusheng Chen 

机构地区：[1]Key Laboratory of National Forestry and Grassland Administration on Forest Ecosystem Protection and Restoration of Poyang Lake Watershed,Jiangxi Agricultural University,Nanchang,330045,China [2]Jiangxi Forestry Resources Monitoring Center,Nanchang,330045,China [3]Postdoctoral Research Station of Management Science and Engineering,Nanchang University,Nanchang,330031,China [4]Jiangxi Provincial Key Laboratory of Silviculture,College of Forestry,Jiangxi Agricultural University,Nanchang,330045,China

出　　处：《Forest Ecosystems》2022年第5期701-709,共9页森林生态系统（英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant Nos.32171759,31730014).

摘　　要：Background:The replanting of broadleaved trees in pure coniferous plantations is widely implemented,as mixed plantations are generally more stable and functional.However,the effect of interspecific interactions between broadleaved and coniferous trees on internal nutrient cycles of conifers remains unclear.Methods:We selected pure coniferous plantations of a native(Pinus massoniana)and an exotic(P.elliottii)pine species and their corresponding mixed plantations with broadleaved trees(Schima superba)in subtropical China,and measured the nitrogen(N)and phosphorus(P)contents in the rhizosphere soils,fine roots,twigs,needles and needle litter of pines.We calculated the root capture,needle resorption and translocation of N and P by pines to determine the mobility of nutrients in trees.Results:Although the N and P in the rhizosphere soils increased due to the replanting of broadleaved trees,the N and P contents in the aboveground tissues of the two pine species did not increase in mixed plantations.Mixed planting had a negative effect on the N and P capture of native pine and a positive effect on that of exotic pine.The N and P resorption efficiencies increased in native pine but were unchanged in exotic pine after the replanting of S.superba.Native pine preferentially employed an aboveground nutrient resorption strategy,whereas exotic pine tended to adopt a belowground nutrient capture strategy after replanting.Translocation of N and P in trees was detected,which reflected the trade-offs between root nutrient capture and needle nutrient resorption.Conclusions:The effect of mixed planting varied between the species of native and exotic pines,and the internal nutrient cycles of both pine species might be dominated by interspecific interaction effects on nutrients rather than soil nutrients.Our study highlights the importance of selecting suitable broadleaved species for replanting in coniferous plantations.

关 键 词：Interspecific interaction Mixture effect Needle resorption N and P translocation Root capture 

分 类 号：S718.5[农业科学—林学]